The conflict in Ukraine is expected to dominate the agenda of an EU foreign ministers meeting in the Latvian capital, Riga.

The two days of informal talks started on March 6 amid heightened tension over Moscow's support for separatists in Ukraine and the implementation of the Minsk cease-fire agreement between Ukrainian government forces and the rebels.

More than 6,000 people have been killed since fighting erupted in eastern Ukraine in April 2014, after Russia annexed Ukraine's southern Crimea Peninsula in March.

Kyiv and the West accuse Russia of deploying troops and weaponry in Ukraine’s east, which Moscow denies.

Also on the agenda are preparations for the EU’s Eastern Partnership summit in May.

Ahead of the Riga meeting, EU foreign affairs chief Federica Mogherini said the European Union is ready to step up sanctions against Russia and separatist leaders if necessary but that the implementation of the truce deal reached in Minsk on February 12 is "the way to go forward."

Speaking about the fragile cease-fire between the warring sides, Mogherini said, "For sure the trend is a positive one, even if not perfect."

She said the key issues were to monitor the cease-fire, especially the withdrawal of heavy weapons from the front line by both sides, and to strengthen the Organization for Security and Cooperation in Europe (OSCE) which monitors implementation on the ground.

German Foreign Minister Frank-Walter Steinmeier said the Riga meeting would discuss how to help the OSCE monitoring implementation on the ground, and that more needs to be done to make the cease-fire accord work.

"At the moment, we are trying to accelerate again the process.” Steinmeier said. “That is the issue in the foreground and not the question if there will be new sanctions."

In Warsaw, visiting British Foreign Secretary Philip Hammond urged the West to prepare "a whole range of potential sanctions options, so that we have maximum flexibility, maximum agility and maximum speed in reacting to any provocation."

Hammond and Polish Foreign Minister Grzegorz Schetyna said excluding Russia from the SWIFT international electronic-payments system would be a measure of last resort if the crisis in Ukraine escalates.

"When it comes to sanctions, SWIFT is the nuclear weapon," Schetyna said.

Hammond said discussion on the option was taking place "primarily in the U.S."

Also on March 6, the European Union removed four Ukrainians from a sanctions list due to lack of evidence.

The EU list, announced in March 2014, had targeted 22 Ukrainian officials suspected of embezzling state funds and illegally transferring the funds outside Ukraine. The EU has frozen their assets held in the 28-nation bloc.

Latvia, which currently chairs the EU Council, its Baltic neighbors Estonia and Lithuania, and other NATO members have voiced concern over what they see as Russia's increasingly aggressive attitude.

The alliance has increased its military presence in the Baltic states, holding military drills and training exercises.

Lithuania announced last month it would renew military conscription for the first time since 2008 after a rise in exercises by the Russian military and overflights along its border.

On March 5, Russia announced that more than 2,000 servicemen were taking part in "large-scale" air-defense exercises in southern Russia, Crimea, and the breakaway Georgian regions of Abkhazia and South Ossetia.

In Kyiv, Ukraine’s military said government forces were withdrawing Uragan (Hurricane) multiple-launch rocket systems from the front line in accordance with the Minsk agreement.

The sides in the conflict have given assurances they were complying with pullback requirements, but OSCE monitors complain that they are being obstructed from conducting exhaustive verifications.

Exchanges of fire continue to be reported daily in eastern Ukraine.

Ukrainian military spokesman Andriy Lysenko said four soldiers had been wounded in the past 24 hours.

He also accused separatists of mustering weapons and manpower in several areas in preparation for potential offensives.

In the government-controlled eastern city of Kharkiv, a senior special police officer who is loyal to Kyiv has been injured along with his wife in a car-bomb blast.

Also on March 6, Britain said it planned to supply Ukraine's army with non-lethal military equipment to help it defend itself against what Defense Secretary Michael Fallon called "Russia's aggression."

The equipment, worth $1.3 million, will be gifted to Ukraine in the coming weeks and includes first aid kits, night vision goggles, laptop computers, helmets, and GPS units.